The group of carousers drank and made noise all night in the bar until the security asked them to leave.

carousers 是名词 carouser 的复数形式，由动词 carouse（狂欢、畅饮）加上后缀 -er 构成，表示"参加狂欢的人"或"纵酒作乐者"。carouse 本身源自德语，原指围成一圈饮酒作乐的行为。